Fate is bad for party (6)
I believe the answer is:
fiesta
'for party' is the definition.
(I've seen this in another clue)
'fate is bad' is the wordplay.
'bad' indicates an anagram.
'fate'+'is'='fateis'
'fateis' with letters rearranged gives 'FIESTA'.
(Other definitions for fiesta that I've seen before include "religious celebration" , "Latin American celebration" , "Feast day" , "A Spanish public celebration" , "Festival, fete" .)